/* * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * * Other licenses: * ----------------------------------------------------------------------------- * Commercial licenses for this work are available. These replace the above * ASL 2.0 and offer limited warranties, support, maintenance, and commercial * database integrations. * * For more information, please visit: http://www.jooq.org/licenses * * * * * * * * * * * * * */ package org.jooq.impl; import static java.util.Arrays.asList; import static org.jooq.impl.DSL.inline; import static org.jooq.impl.Keywords.K_AS; import static org.jooq.impl.Keywords.K_CAST; import static org.jooq.impl.Keywords.K_DECIMAL; import static org.jooq.impl.Keywords.K_TRIM; import static org.jooq.impl.SQLDataType.BOOLEAN; import static org.jooq.impl.SQLDataType.DOUBLE; import static org.jooq.impl.SQLDataType.FLOAT; import static org.jooq.impl.SQLDataType.REAL; import static org.jooq.impl.SQLDataType.VARCHAR; import java.sql.Date; import java.sql.Time; import java.sql.Timestamp; import org.jooq.Clause; import org.jooq.Configuration; import org.jooq.Context; import org.jooq.DataType; import org.jooq.Field; import org.jooq.QueryPart; import org.jooq.RenderContext.CastMode; /** * @author Lukas Eder */ final class Cast<T> extends AbstractFunction<T> { /** * Generated UID */ private static final long serialVersionUID = -6776617606751542856L; private final Field<?> field; public Cast(Field<?> field, DataType<T> type) { super("cast", type); this.field = field; } private final DataType<T> getSQLDataType() { return getDataType().getSQLDataType(); } @Override final QueryPart getFunction0(Configuration configuration) { switch (configuration.dialect().family()) { case DERBY: return new CastDerby(); default: return new Native(); } } private class CastDerby extends Native { /** * Generated UID */ private static final long serialVersionUID = -8737153188122391258L; @SuppressWarnings("unchecked") private final Field<Boolean> asDecodeNumberToBoolean() { // [#859] 0 => false, null => null, all else is true return DSL.choose((Field<Integer>) field) .when(inline(0), inline(false)) .when(inline((Integer) null), inline((Boolean) null)) .otherwise(inline(true)); } @SuppressWarnings("unchecked") private final Field<Boolean> asDecodeVarcharToBoolean() { Field<String> s = (Field<String>) field; // [#859] '0', 'f', 'false' => false, null => null, all else is true return DSL.when(s.equal(inline("0")), inline(false)) .when(DSL.lower(s).equal(inline("false")), inline(false)) .when(DSL.lower(s).equal(inline("f")), inline(false)) .when(s.isNull(), inline((Boolean) null)) .otherwise(inline(true)); } @Override public final void accept(Context<?> ctx) { // Avoid casting bind values inside an explicit cast... CastMode castMode = ctx.castMode(); // [#857] Interestingly, Derby does not allow for casting numeric // types directly to VARCHAR. An intermediary cast to CHAR is needed if (field.getDataType().isNumeric() && VARCHAR.equals(getSQLDataType())) { ctx.visit(K_TRIM).sql('(') .visit(K_CAST).sql('(') .visit(K_CAST).sql('(') .castMode(CastMode.NEVER) .visit(field) .castMode(castMode) .sql(' ').visit(K_AS).sql(" char(38))") .sql(' ').visit(K_AS).sql(' ') .sql(getDataType(ctx.configuration()).getCastTypeName(ctx.configuration())) .sql("))"); return; } // [#888] ... neither does casting character types to FLOAT (and similar) else if (field.getDataType().isString() && asList(FLOAT, DOUBLE, REAL).contains(getSQLDataType())) { ctx.visit(K_CAST).sql('(') .visit(K_CAST).sql('(') .castMode(CastMode.NEVER) .visit(field) .castMode(castMode) .sql(' ').visit(K_AS).sql(' ').visit(K_DECIMAL) .sql(") ") .visit(K_AS) .sql(' ') .sql(getDataType(ctx.configuration()).getCastTypeName(ctx.configuration())) .sql(')'); return; } // [#859] ... neither does casting numeric types to BOOLEAN else if (field.getDataType().isNumeric() && BOOLEAN.equals(getSQLDataType())) { ctx.visit(asDecodeNumberToBoolean()); return; } // [#859] ... neither does casting character types to BOOLEAN else if (field.getDataType().isString() && BOOLEAN.equals(getSQLDataType())) { ctx.visit(asDecodeVarcharToBoolean()); return; } super.accept(ctx); } } private class Native extends AbstractQueryPart { /** * Generated UID */ private static final long serialVersionUID = -8497561014419483312L; @Override public void accept(Context<?> ctx) { // Avoid casting bind values inside an explicit cast... CastMode castMode = ctx.castMode(); // Default rendering, if no special case has applied yet ctx.visit(K_CAST).sql('(') .castMode(CastMode.NEVER) .visit(field) .castMode(castMode) .sql(' ').visit(K_AS).sql(' ') .sql(getDataType(ctx.configuration()).getCastTypeName(ctx.configuration())) .sql(')'); } @Override public final Clause[] clauses(Context<?> ctx) { return null; } } }